There has been a lot of debate on several manga forums I visit debating whether Red River is a retelling of Ouke no Monshou.

Red river is not a retelling, but was inspired by Ouke no Monshou.
Chie Shinohara has stated in interviews that is a huge fan of Chieko Hosokawa.
The rumor among mangaka is that Red River first issue initially was meant as a gift for Hosokawa, but Hosokawa insisted that Shinohara publish it instead.

Many modern Mangaka respect Hosokawa, who has been a professional mangaka since 1958.

There is also plenty of heated arguments for and against whether Kail from Red River and Ishimin are the same person.

No, Kail is not Ishimin.
In Red River, It is mentioned that Kail, as Mursilli II, was destined to become as great as his ancestor, Mursilli I.
Ishimin would be Mursilli I.

The evidence is simple.
Historicaly, Hattusa, the capital of Hatti (sometimes called Hitta) is first occupied by Hattusilli I, after his former capital on the coast was destroyed by an earthquake and subsequent fire.

In Ouke no Monshou, Hattusa is newly constructed and declared the capital by Ishimin's father, Hattusilli.
In Red River, Hattusa has long been established as the Hittite capital.

Honestly, I read on Sunday Red River....yeah I know.... all in one day.....I was entangled.... loved Kail-sama.....
anyway then I found Ouke no Monshou....
Imagine after a whole day.... of Yuuri Ishtar... and all the fights....
to see sweet Carol.... I know she knows her history and iron making... but she is soooo but sooo defenseless...
that is what pisses me off so much....

I'm going to read this this the end.... but I hate how Carol tortures Memphis... well I'm just on vol 13... but already with the NO-NO lights,
I uderstand her that she's afraid of him but he is just rough, I won't say he is a tyrant - he was the pharaoh so that's why he might act a little more arrogant and shouts a lot.
even the

Spoiler Alert! Click to show or hide

moment when his father's tomb was disturbed and he killed those men... well now.... any child would do that for a parent...they disturbed his father's resting place... it annoys me just thinking about it... I don't say kill them but.... those where the times, no?

I never made any connections between the 2 stories...
I mean Ouke no Monshou is Ouke no Monshou and Red River is Red River lol
In Red River the love thing is more mature or I'd say more present, while here it's more platonic - until vol13 - and cute and ..
umm... less passionate that's the expression I was searching for.

And I think people well normal people should realise, even if they don't know history or if they don't know of Egypt or Turkey/The Hittite Empire, that Kail is not Ishimin.
I searched and there is no pharaoh Memphis (only the city), I don't know if there is a legend...http://www.touregypt.net/kings.htm
well not until Tutankhamun and Ramses. SO it's a made up thing.
Also isn't Isis a great goddess... like Cleopatra thought of herself as Isis's daughter.
SO, yeah whenever I start reading a historical manga/drama, I always look up a few bits and pieces on the period... just so I get in the atmosphere of that time....
To my shame... I didn't know about the Hittite Empire.... I heard of Anatolia... but I wasn't aware of the fact that that was the place of the Hittites. And it's next to my country..figure that....

<<<to see sweet Carol.... I know she knows her history and iron making... but she is soooo but sooo defenseless...
that is what pisses me off so much....>>>

The only thing about Carol that I can say is that she was a product of the time her character was initially concieved. Even though women's liberation was in full swing in 1970's, it was still considered normal in most highly developed countries for a woman to be defenseless and dependent. She could be a career woman, but she still was expected to be ladylike and demure. She was still expected to let a man save her.
It seems that as the story progresses some, Carol gets a little more self reliant.

It's true, Memphis' name is based on the old Egyptian capital, but he seems to be based loosely on Pharoh Khafra.
Khafra isn't too catchy of a name, plus, when spelled out in Kana and sounded back, it's obscene.

Khafra's first wife,Meresankh III is rumored to have been his sister. She, likely because her and Khafra's parents were also brother and sister, was always sickly and died early.
Khafra's second wife (consort) was Khamarernebty I. Little is known about her except that she consulted her husband on matters of importance and seemed to have keen insight on subjects women normally didn't concern themselves with.
It is suspected that Khamarernebty had been a former slave and servant of Meresakh.

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It's not easy to destroy the capital city of Assyria and know at the same time that innocent citizens will get caught in the destruction.
In my opinion, this it the turning point for Carol.
She slowly begins to realize that even though she's been taught that she has to be rescued by a man, there are some things she has to do for herself.
She also begins to understand that many times the choice to kill or sanction the killing of others is a necessary evil that a ruler, especially in the ancient world, can't avoid. When, who, how and how often the killing occurs historically often separates a good ruler from a bad one.

I'm a big history buff as well.
A number of years ago, an old college friend invited me to stay at her place in Van, Turkey for a couple of weeks. It was absolutely amazing.
Basima gave me the whole tourist tour, plus we got to explore some 'city caves.' Turkey has dozens of underground cities and may of them are still intact.